1978 avenger 17' with 200 merc want to go faster

[Fatmanlittleski]

just bought this boat and it has a 17 pitch stainless prop but will only go 45 mph can and should it go faster

[282]

yes it should be in the 60's easy. post up some pictures, great boats.

[SS Minnow]

I know nothing about your boat, but I had a 78 or 79 invader with a same year inline 6 115 on it with a 17p aluminum prop and I was running maybe 40 mph or so. My boat was a deep v heavy old tub. Floor was soaked, core probably was too.

So yeah, you have a ways to go with your set-up. You should moving a bit faster then what you are.Especially if this is close to what you have:

[Fatmanlittleski]

[282]

Nice looking Avenger, wonder if set back with a jack plate would help with that. The motor has been gone thru? Hull not wet? Firing on all cylinders?? 45 seems awfully slow for that boat. Where are you located?

[Merc 2.5]

17 pitch and 17ft boat the rpm has gotta be thru the roof at wot? Need find u a 24 or 25 I would think

[DangerNewb]

17 pitch and 17ft boat the rpm has gotta be thru the roof at wot? Need find u a 24 or 25 I would think

Absolutely. You're running around stuck in 2nd gear. Get some more pitch. I'd think you could pull a 26 pitch prop. Will slow down your hole shot and acceleration but cruise and top end will be much better. Not sure what the WOT rpm target is on your motor but id guess mid 6k range. You want as much pitch as your motor will pull and still be able to hit the targeted rpm on top. Other considerations need to he addressed also, but 17 pitch is for a big heavy boat or slow underpowered boats.

[Merc 2.5]

My bass rig is on heavy side 19.5ft , I run a modified 25 (runs more like 26) and it's my everything prop , I can put 2 more people and gear and still hit target rpm , u dont wanna max out ur motor/prop for 1 person , cause when u add a person or 2 it will bring rpm down and u still wanna be able to get to the 5800 range atleast. I'm around 6300 ish with just me and 5800 5900 with people ,coolers, etc. My 28 chopper is perfect with just me but when I add 1 other person it's to much. Hope that helps some. Also need just double check fire and fuel and make sure everything up to par. Good luck

[Fatmanlittleski]

i no nothing about the boat im in Lebanon Oregon i bought it and it was not running got it to fire on all cylinders and installed a new water pump impeller

[SS Minnow]

Well, you are headed in the right direction. Now you just need to find the right prop and motor height, maybe even a little set back.

[hsbob]

what is the width of the pad if it has one. without a pad 60mph is your limit, it will chime walk.

a boat like that with a 200 should go 65-74mph with a 8" setback and a jack plate at 1" below the bottom the rpm should be around 6200. that should be your rpm limit with stock oil mixing. the plastic gears are the issue with the pump. it should have steel races on crank bearing so with mixed gas 7000 is ok.

[Fatmanlittleski]

cool thanks changed the prop last night from a 17 pitch to a 25 pitch didn't really change much

[DangerNewb]

cool thanks changed the prop last night from a 17 pitch to a 25 pitch didn't really change much

Does your tach work? No way you had same speed and rpm with a 17 vs 25. Possible to get same speed but rpm had to be way different. Assuming your motor wouldn't turn the 25 anywhere close to 6k?

[David - WI]

Or it's trimmed "full down" the whole time.

[DangerNewb]

Or it's trimmed "full down" the whole time.

Possible. Not saying that's what is going in here but standing joke between my brother and I is, "that button is only for putting it on the trailer", when we see folks plowing the bow.